1. Field of the Invention
The present invention relates to a suturing needle with suture used in a surgical operation and a method of producing the same. More specifically, it relates to the suturing needle with suture formed of a hollow tube and a core material inserted thereinto and its production method. The inner core material inserted into the suturing needle is fixed to its tip and root to prevent broken pieces from scattering when the needle is broken to pieces from a body tissue.
2. Description of the Prior Art
Two types of surgical suturing needle are known when classified roughly. One is an eyed type and the other is an eyeless type.
As the eyed type suturing needle, the one disclosed, for example, in Japanese Utility Model Publication No. Sho 46-12549 (12549/1971) is well known. In this type of suturing needle, a threading hole is provided at the end on its root side. A suture is adapted to be inserted through the threading hole of the needle at operation.
On the other hand, as the eyeless type suturing needle, the one disclosed, for example, in Japanese Patent Publication No. Sho 59-15648 (15648/1984) is well known. In this type of suturing needle, the suture is bound integrally with the suturing needle beforehand at production. When producing the suturing needle, first a prepared hole having a diameter smaller than the suture is opened on the end surface of the needle root. Thereafter, the prepared hole is expanded into a binding hole having the same or larger diameter than the suture. Then the suture is inserted into the binding hole to be bound integrally with the suturing needle by caulking.
Also, as a modified example of the eyeless type, the one disclosed, for example, in Japanese Patent Publication No. 61-103438 (103438/1986) is known. In this type of suturing needle, a groove for the suture is provided generally throughout the whole length of the suturing needle. The portion of suture inserted into the groove is fixed to the suturing needle by caulking and formed as the suturing needle with suture.
However, in the conventional suturing needle, problems mentioned hereinbelow are encountered.
(1) In the first eyed type suturing needle, it is not only troublesome to thread the suture through the threading hole at every operation, but the body tissue is also susceptible to damage during operation, since the suture portion threaded through the threading hole and folded back exceeds a size of the needle.
Also, when the suturing needle is broken for various reasons, broken pieces are scattered and remain in the body tissue. Besides as it is troublesome to extract these broken pieces, the operation may be badly affected.
(2) In the second eyeless type suturing needle, it necessitates a skilled technique to open the prepared hole in the end surface on the root side of the needle having a reduced diameter, or to expand it further to a prescribed size.
Also, during boring the hole, a drill is susceptible to damage, resulting in a high machining cost.
Besides, if the needle is broken during operation, the same inconvenience as mentioned in the eyed type is created.
(3) In a modified example of the second eyeless type, since a flaw due to the groove aforementioned remains generally throughout the whole length of the suturing needle on its surface, the surface can not be finished finely.
Besides, this type of suturing needle is made of a plate material and thus grinding of its tip, lip or the like is insufficient. Therefore, the sharpness (smooth penetration into the tissue) of the needle is deteriorated and becomes impractical.
In addition, when giving heat treatment to harden the suturing needle during production, since the suture fixed to the suturing needle beforehand is susceptible to damage due to a high heat treatment temperature conducted through the groove, it is difficult to increase the hardness and strength by the heat treatment.